No abstract

The role of wildlife such as wild birds, macaques, and bats in the spreading and maintenance of deadly zoonotic pathogens in nature have been well documented in many parts of the world. One such pathogen is the mosquitoes borne virus, namely the West Nile Virus (WNV). Previous research has shown that 1:7 and 1:6 Malaysian wild birds are WNV antibody and RNA positive, respectively, and bats in North America may not be susceptible to the WNV infection. This study was conducted to determine the status of WNV in Malaysian macaques and bats found in mangrove forests and caves, respectively. Archive sera and oropharyngeal swabs from long-tailed macaques were subjected to the antibody detection using WNV competitive enzyme-linked immunosorbent assay (c-ELISA) and WNV RNA using RT-PCR, respectively, while the archive oropharyngeal and rectal swabs from bats were subjected to RT-PCR without serological analysis due to the unavailability of serum samples. The analysis revealed a WNV seropositivity of 29.63% (24/81) and none of the macaques were positive for WNV RNA. Meanwhile, 12.2% (5/41) of the bats from Pteropodidae, Emballonuridae, and Rhinolophidae families tested positive for WNV RNA. Here, we show a high WNV antibody prevalence in macaques and a moderate WNV RNA in various Malaysian bat species, suggesting that WNV circulates through Malaysian wild animals and Malaysian bat species may be susceptible to the WNV infection.

West Nile virus is a mosquito-borne neurotropic pathogen with a wide host range that constitutes a significant risk to public and animal health. There is limited information on WNV infection in domesticated mammals in Malaysia; however, current reports indicate infections in birds, macaques, bats and pigs from Malaysia. In this study, 203 serum samples from cattle, goats, and horses were tested for the presence of anti-WNV IgG using a competitive enzyme-linked immunosorbent assay (c-ELISA). Additionally, using one-step RT-PCR, nasopharyngeal swabs were analyzed for WNV RNA from all 203 animals in this study. The WNV seroprevalence was 32.53% (27/83) at 95% CI (0.2342–0.4319) in cattle, 48.27% (14/29) at 95% CI (0.3139–0.6557) in goats and 53.84% (49/91) at 95% CI (0.4366–0.6373) in horses. Cross-reactive JEV antibodies were detected in two cattle and 34 horses. None of the cattle or goats tested positive for WNV RT-PCR. Seven horses were positive for WNV RT-PCR, a molecular prevalence of 7.69% (7/91) at 95% CI (0.0353–0.1528). This is the first reported detection of WNV in domesticated mammals of Malaysia, a significant addition to the growing evidence that WNV is being transmitted from vectors to susceptible hosts in Malaysia.